Tillage and nutrient source effects on surface and subsurface water quality at corn planting

This study quantified the effects of tillage (moldboard plowing [MP], ridge tillage [RT]) and nutrient source (manure and commercial fertilizer [urea and triple superphosphate]) on sediment, NH4+ -N, NO3- -N, total P, particulate P, and soluble P losses in surface runoff and subsurface tile drainage from a clay loam soil. Treatment effects were evaluated using simulated rainfall immediately after corn (Zea mays L.) planting, the most vulnerable period for soil erosion and water quality degradation. Sediment, total P, soluble P, and NH4+ -N losses mainly occurred in surface runoff. The NO3- -N losses primarily occurred in subsurface tile drainage. In combined (surface and subsurface) flow, the MP treatment resulted in nearly two times greater sediment loss than RT (P < 0.01). Ridge tillage with urea lost at least 11 times more NH4+ -N than any other treatment (P < 0.01). Ridge tillage with manure also had the most total and soluble P losses of all treatments (P < 0.01). If all water quality parameters were equally important, then moldboard plow with manure would result in least water quality degradation of the combined flow followed by moldboard plow with urea or ridge tillage with urea (equivalent losses) and ridge tillage with manure. Tillage systems that do not incorporate surface residue and amendments appear to be more vulnerable to soluble nutrient losses mainly in surface runoff but also in subsurface drainage (due to macropore flow). Tillage systems that thoroughly mix residue and amendments in surface soil appear to be more prone to sediment and sediment-associated nutrient (particulate P) losses via surface runoff.     

A new method for spectrophotometric determination of benzene in air

A new spectrophotometric method for the determination of benzene in air is described. The method is based upon the nitration of benzene to m-dinitrobenzene and subsequent reduction to m-phenylenediamine. m-Phenylenediamine is determined by diazotization-coupling reaction. α-Naphthol is used as a coupling reagent. Beer's law is obeyed in the range of 10–80 μg of m-dinitribenzene per 25 mL sample. The dye shows a wavelength of maximum absorption at 530 nm. The dye is stable for ～ 30 h. Toluene, the major interferent, can be separated. Beer's law, sensitivity, reproducibility, and other reaction conditions such as time, temperature, and acidity were studied. Formation of stable dye is the main advantage of the method over the butanone method for benzene, in which the colored complex is stable for only 5 min. It is possible to determine traces of benzene (0.05–0.30 μg/mL) by extracting the azo dye in 10 mL iso-amyl alcohol; this also increases the stability of the dye up to 42 h.     

Implementing REDD+ (Reducing Emissions from Deforestation and Degradation): evidence on governance,evaluation and impacts from the REDD-ALERT project

The REDD-ALERT (Reducing Emissions from Deforestation and Degradation from Alternative Land Uses in the Rainforests of the Tropics) project started in 2009 and finished in 2012, and had the aim of evaluating mechanisms that translate international-level agreements into instruments that would help change the behaviour of land users while minimising adverse repercussions on their livelihoods. Findings showed that some developing tropical countries have recently been through a forest transition, thus shifting from declining to expanding forests at a national scale. However, in most of these (e.g. Vietnam), a significant part of the recent increase in national forest cover is associated with an increase in importation of food and timber products from abroad, representing leakage of carbon stocks across international borders. Avoiding deforestation and restoring forests will require a mixture of regulatory approaches, emerging market-based instruments, suasive options, and hybrid management measures. Policy analysis and modelling work showed the high degree of complexity at local levels and highlighted the need to take this heterogeneity into account—it is unlikely that there will be a one size fits all approach to make Reducing Emissions from Deforestation and Degradation (REDD+) work. Significant progress was made in the quantification of carbon and greenhouse gas (GHG) fluxes following land-use change in the tropics, contributing to narrower confidence intervals on peat-based emissions and their reporting standards. There are indications that there is only a short and relatively small window of opportunity of making REDD+ work—these included the fact that forest-related emissions as a fraction of total global GHG emissions have been decreasing over time due to the increase in fossil fuel emissions, and that the cost efficiency of REDD+ may be much less than originally thought due to the need to factor in safeguard costs, transaction costs and monitoring costs. Nevertheless, REDD+ has raised global awareness of the world’s forests and the factors affecting them, and future developments should contribute to the emergence of new landscape-based approaches to protecting a wider range of ecosystem services.     

Drainage Impacts on Surficial Water Retention Capacity of a Prairie Pothole Watershed

Wetland restoration has been proposed as a tool to mitigate excess runoff and associated nonpoint source pollution in the Upper Midwestern United States. This study quantified the surficial water retention capacity of existing and drained wetlands for the Greater Blue Earth River Basin (GBERB), an intensively drained agricultural watershed. Using airborne light detection and ranging, the historic depressional storage was determined to be 152 mm. Individual depression analysis suggested that the restoration of most drained areas would have little impact on the storage capacity of the GBERB because the majority (53%) of retention capacity was in large depressions (>40 ha) which comprised only a small proportion (<1.0) of the observed depressions. Accounting for change in storage and the difference in annual evapotranspiration (ET) between wetlands and the croplands that replaced them, restoration of all depressions in the Minnesota portion of GBERB would provide a maximum of 131 mm additional capacity over and above the modern day capacity (193 mm; 56 mm depressional storage; 60 mm wetland ET; and 77 mm cropland ET). Considering that depressional depths in smaller areas are within the range of uncertainty of the lidar digital elevation models and larger depressions have the most storage, we conclude that efforts to increase the surficial water‐holding capacity of the GBERB would be best served in the restoration of large (>40 ha) depressions.     

Assessment of mechanical,durability and microstructural properties of geopolymer concrete containing ceramic tile waste

Journal of Material Cycles and Waste Management - The amount of ceramic waste being generated is increasing day by day, and ceramic waste management is one of the most challenging issues for many...     

Optimal sizing of different configuration of photovoltaic,fuel cell,and biomass-based hybrid energy system

Environmental Science and Pollution Research - The need for power is rising on a daily basis all across the world. Due to the finite supply of fossil fuels, it is critical to develop innovative...     

Water toxicants: a comprehension on their health concerns,detection, and remediation

Environmental Science and Pollution Research - Water is an essential moiety for the human use since a long time. Availability of good-quality water is very essential, as it is used in almost all...